Heat conduction pipe

ABSTRACT

A heat conduction pipe includes an outer pipe ( 10 ), a plurality of inner pipes ( 20 ), and a pair of plugs ( 30 ). The outer pipe is made of a material having great heat conductivity, and defines a pair of openings in respective opposite ends thereof. Each inner pipe is a sealed vacuum pipe made of a material having great heat conductivity, and contains liquid work medium having great heat conductivity. The inner pipes are received in the outer pipe. The plugs seal the openings of the outer pipe and engage with the inner pipes. Liquid work medium having great heat conductivity is movably accommodated in the outer pipe.

BACKGROUND OF THE INVENTION

[0001] 1. Field of the Invention

[0002] The present invention relates to heat conduction pipes, and more particularly to a heat conduction pipe which has a plurality of inner pipes received in an outer pipe that has a large thermal contact surface.

[0003] 2. Description of Related Art

[0004] During operation of many heat generating devices such as central processing units (CPUs), large amounts of heat are produced. Such heat must be quickly removed from the heat generating device, to prevent the heat generating device from becoming unstable or being damaged. Typically, a heat sink is directly attached to an outer surface of a heat generating device to remove heat therefrom.

[0005] A conventional heat sink comprises a chassis and a plurality of fins extending upwardly from the chassis. The chassis of the heat sink is attached on the outer surface of the heat generating device. The chassis absorbs heat from the heat generating device, and the absorbed heat is conducted to the fins. The heat is thus dissipated. However, the heat sink is conventionally made from aluminum or aluminum alloy. Therefore the inherent heat conductivity of the heat sink is limited. Modern electronic devices such as high-speed CPUs frequently generate copious amounts of heat. The inherent heat conductivity of the heat sink is often not sufficient to adequately dissipate heat from the heat generating device.

[0006] An alternative heat dissipation device has been developed to achieve greater heat dissipation capability. The heat dissipation device comprises a plurality of parallel fins and a heatpipe. The heatpipe is extended through the fins. One end of the heatpipe is attached to the heat generating device, to be in intimate thermal contact therewith. However, the thermal contact surface of the end of the heatpipe is limited by the diameter of the heatpipe. The heatpipe is conventionally a vacuum pipe, which cannot easily be made to have a large diameter. Accordingly, the heat conducting capability of the heat dissipation device is frequently not sufficient. To obtain a larger thermal contact surface, a plurality of heatpipes is employed. However, this makes assembly of the heatpipes and the fins more difficult, and adds to costs.

[0007] It is strongly desired to provide an improved heat conduction pipe which overcomes the above-mentioned problems.

SUMMARY OF THE INVENTION

[0008] Accordingly, an object of the present invention is to provide a heat conduction pipe which comprises a plurality of inner pipes and an outer pipe receiving the inner pipes therein.

[0009] Another object of the present invention is to provide a heat conduction pipe which has a large thermal contact surface.

[0010] A further object of the present invention is to provide a heat conduction pipe which can be readily manufactured.

[0011] In order to achieve the objects set out above, a heat conduction pipe of the present invention comprises an outer pipe, a plurality of inner pipes and a pair of plugs. The outer pipe is made of a material having great heat conductivity, and defines a pair of openings in respective opposite ends thereof. Each inner pipe is a sealed vacuum pipe made of a material having great heat conductivity, and contains liquid work medium having great heat conductivity. The inner pipes are received in the outer pipe. The plugs seal the openings of the outer pipe and engage with the inner pipes. Liquid work medium having great heat conductivity is movably accommodated in the outer pipe.

[0012] Other objects, advantages and novel features of the present invention will become more apparent from the following detailed description when taken in conjunction with the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

[0013]FIG. 1 is an exploded perspective view of a heat conduction pipe in accordance with the present invention;

[0014]FIG. 2 is an assembled view of the heat conduction pipe of FIG. 1; and

[0015]FIG. 3 is a schematic side plan view of the heat conduction pipe of FIG. 2 engaged with a plurality of parallel fins and attached on a heat generating electronic device.

DETAILED DESCRIPTION OF THE INVENTION

[0016] Reference will now be made to the drawing figures to describe the present invention in detail.

[0017] Referring to FIGS. 1 and 2, a heat conduction pipe of the present invention comprises an outer pipe 10, a plurality of inner pipes 20 and a pair of plugs 30.

[0018] The outer pipe 10 has relatively large dimensions, and is made of a material having great heat conductivity. The outer pipe 10 comprises a first vaporizing end 12 and an opposite first condensation end 14. A pair of openings (not labeled) is respectively defined in the first vaporizing end 12 and the first condensation end 14. Each inner pipe 20 has relatively small dimensions. Each inner pipe 20 is a sealed vacuum pipe made of a material having great heat conductivity, and contains liquid work medium having great heat conductivity. The work medium can be transformed between liquid form and vapor form during heating or cooling thereof. Each inner pipe 20 comprises a second vaporizing end 22, and an opposite second condensation end 24. Each plug 30 is a thin disc-shaped plate. A plurality of cavities 32 is defined in an inner face of each plug 30, for respectively engaging with ends of the inner pipes 20 and thereby positioning the inner pipes 20. Liquid work medium having great heat conductivity is also provided for the outer pipe 10. The work medium can be transformed between liquid form and vapor form during heating or cooling thereof.

[0019] Referring also to FIG. 2, in assembly, the inner pipes 20 are received in the outer pipe 10. Each second vaporizing end 22 corresponds to the first vaporizing end 12. Each second condensation end 24 corresponds to the first condensation end 22. One plug 30 is engagingly plugged into one opening of the outer pipe 10. Corresponding ends of the inner pipes 20 are engagingly received in the cavities 32 of said one plug 30. The work medium is introduced into the outer pipe 10. The other plug 30 is engagingly plugged into the other opening of the outer pipe 10, to seal the outer pipe 10. The heat conduction pipe is thus fully assembled.

[0020] Referring also to FIG. 3, in use, the heat conduction pipe is extended perpendicularly through a plurality of heat sink fins 40 which are parallel to a heat generating electronic device 50. The vaporizing end 12 of the outer pipe 10 and the corresponding plug 30 intimately contact the electronic device 50. The second condensation ends 24 of the inner pipes 20 are submerged in the work medium of the outer pipe 10. In operation of the heat conduction pipe, the work medium in the first vaporizing end 12 of the outer pipe 10 is heated and forms vapor. The vapor rises to the first condensation end 14 of the outer pipe 10. The vapor accumulated at the first condensation end 14 is cooled back to liquid form and falls back to the first vaporizing end 12. At the same time, heat in the work medium of the outer pipe 10 is transferred to the inner pipes 20. The work medium in the second vaporizing ends 22 of the inner pipes 20 is heated and forms vapor. The vapor rises to the second condensation ends 24 of the inner pipes 20. The vapor accumulated at the second condensation ends 24 is cooled back to liquid form and falls back to the second vaporizing ends 22. The work medium thus continually circulates in the outer and inner pipes 10, 20. Heat transferred to the heat conduction pipe from the electronic device 50 is quickly and efficiently dissipated.

[0021] In the present invention, the plurality of inner pipes 20 is received in the outer pipe 10. The second vaporizing ends 22 of the inner pipes 20 are submerged in the work medium of the outer pipe 10. The outer pipe 10 and said corresponding plug 30 provide the heat conduction pipe with a large surface area for intimate thermal contact with the electronic device 50. This gives the heat conduction pipe great heat dissipation capability. Furthermore, the outer pipe 10 of the heat conduction pipe can be readily manufactured.

[0022] It is to be understood, however, that even though numerous characteristics and advantages of the present invention have been set forth in the foregoing description, together with details of the structure and function of the invention, the disclosure is illustrative only, and changes may be made in detail, especially in matters of shape, size, and arrangement of parts within the principles of the invention to the full extent indicated by the broad general meaning of the terms in which the appended claims are expressed. 

What is claimed is:
 1. A heat conduction pipe comprising: an outer pipe defining an opening at an end thereof, the outer pipe being made of a material having great heat conductivity; an inner pipe received in the outer pipe, the inner pipe being a vacuum pipe made of a material having great heat conductivity; and a plug sealing the opening of the outer pipe and engaging with the inner pipe.
 2. The heat conduction pipe as claimed in claim 1, wherein the outer pipe comprises a first vaporizing end and a first condensation end.
 3. The heat conduction pipe as claimed in claim 2, wherein the inner pipe comprises a second vaporizing end corresponding to the first vaporizing end, and a second condensation end corresponding to the first condensation end.
 4. The heat conduction pipe as claimed in claim 1, wherein work medium having great heat conductivity is movably accommodated in the outer pipe, and wherein the second vaporizing end of the inner pipe is submerged in the work medium of the outer pipe.
 5. The heat conduction pipe as claimed in claim 1, wherein the outer pipe defines a pair of openings at respective opposite ends thereof.
 6. The heat conduction pipe as claimed in claim 1, wherein the plug defines a cavity engagingly receiving an end of the inner pipe so that the inner pipe is positioned in the outer pipe.
 7. A heat dissipation assembly comprising: a heat generating device; a plurality of heat sink fins; and a heat conduction pipe extended through the heat sink fins, the heat conduction pipe comprising an outer pipe and a plurality of inner pipes parallel to and received in the outer pipe, the outer and inner heat pipes each containing work medium having great heat conductivity, an end of the outer pipe being in thermal contact with the heat generating device.
 8. The heat dissipation assembly as claimed in claim 7, wherein each of the inner pipes is a vacuum pipe.
 9. The heat dissipation assembly as claimed in claim 7, wherein the heat sink fins are parallel to the heat generating electronic device.
 10. The heat dissipation assembly as claimed in claim 7, wherein the heat conduction pipe extends perpendicularly through the heat sink fins.
 11. The heat dissipation assembly as claimed in claim 7, wherein ends of the inner pipes corresponding to said end of the outer pipe are submerged in the work medium of the outer pipe.
 12. A heat conduction pipe apparatus comprising: an outer pipe having a larger diameter and defining opposite first vaporizing and first condensing ends; a plurality of inner pipes evenly dispensed in said outer pipe each having a smaller diameter and defining opposite second vaporizing and second condensing ends corresponding to said first vaporizing and first condensing ends; sealing caps secured to ends of the outer pipe and ends of the inner pipes; and work medium filled between an interior of the outer pipe and an exterior of the inner pipe, and within an interior of the inner pipe. 